Apparatus for drilling large diameter holes

ABSTRACT

Drilling of large diameter holes in the earth devices accomplished by means of a plurality of small drilling devices which move along a traversing bar to drill a number of small contiguous holes, said bar being rotatable about an anchored pilot shaft to complete the cylindrical cut, the force required to cut into the earth being provided by the weight of the hole casing which is borne by the traversing bar and by pressure exerted against the pilot shaft.

United States Patent APPARATUS FOR DRILLING LARGE DIAMETER HOLES 8Claims, 5 Drawing Figs.

US. Cl 175/91, 175/96, 175/97 Int. Cl EZlb 3/08, E2lb 7/00, E21b 11/00FieldofSearch 175/57, 62,

[56] References Cited UNITED STATES PATENTS 3,169,590 2/1965 Thatcher175/94 3,310,124 3/1967 Farmer 175/95 X 3,376,942 4/1968 Van Winkle.....175/94 X 3,477,762 11/1969 Frenyo et al 175/62 X Primary Examiner-DavidH. Brown Attorneys-Harry M. Saragovitz, Edward J. Kelly, Herbert Berland Lawrence E. Labadini ABSTRACT: Drilling of large diameter holes inthe earth devices accomplished by means of a plurality of small drillingdevices which move along a traversing bar to drill a number of smallcontiguous holes, said bar being rotatable about an anchored pilot shaftto complete the cylindrical cut, the force required to cut into theearth being providedby the weight of the hole casing which is borne bythe traversing bar and by pressure exerted against the pilot shaft.

PATENTED JULZO I971 SHEET 3 OF 3 APPARATUS FOR DRILLING LARGE DIAMETERHOLES This isa divisional application of U.S. Pat. application Ser. No.812,165, filed Apr. 1, 1969, for Method And Apparatus For Drilling LargeDiameter Holes," inventor, Jack V. Tedrow..

The invention described herein may be manufactured, used, and licensedby or for the Government for governmental purposes without the paymentto me of any royalty thereon.

This invention relates to a novel method and apparatus for drillinglarge cylindrical openings or holes in the earth. Such openings can beused for numerous purposes such as underground silos or storagecompartments, concealed gun mounts, imbedded missilepads, mining shaftsand the like. In addition, my invention could be used in undergroundrescue operations to retrieve trapped miners.

In the past, there has been a problem with drilling large diameter holesor boreholes in remote areas. In addition, it has been very difficult tomove this drilling equipment quickly from one place to another. The mainreason for these problems is the extreme size and weight required inthese large diameterhole drills. It is not uncommon for the drill collaron one of these conventional drills to weigh 300,000 pounds. Thisextreme size and weight makes it very difficult and expensive to movethedrilling equipment and it is almost impossible to take this equipmentinto remote areas.

I havediscovered that the above problem may be solved by eliminating themassive drill collar used by conventional drill rigs. This isaccomplished by drilling several small diameter holes, the sum being alarge diameter hole, which does not require the drill collar. Myinvention would make it possible for the drilling equipment to be movedor flown into remote areas to be flown from one place to another in ashort period of time.

In view of the above, the primary object of my invention is to provide anovel method and apparatus for drilling a large diameter hole. 1

A further object of this invention is to provide a novel method andapparatus for drilling large diameter holes whereby this may beaccomplished without the use of extremely heavy drilling equipment.

A further object of the invention is to provide a novel method andapparatus for drilling large diameter holes whereby the equipment may bemoved in a reasonable fashion. 1

A further object of my invention 'is to provide a novel method andapparatus for drilling large diameter holes whereby a series ofcontiguous small diameter holes form a large diameter hole. 1

With the foregoing objects in view and such other objects and advantagesas will become apparent to those skilled in the art to which thisinvention relates as this specification proceeds, my invention consistsessentially in the arrangement and construction of parts all ashereinafter more particularly described, reference being had toaccompanying drawings.

FIG. 1, is a side elevation showing the overall apparatus of thisinvention.

FIG. 2 is a top section taken along the line 22.

FIG. 3 is a side section taken along line 3-3 in the direction of thearrows and showing in greater detail a portion of the structureillustrated in FIG. 1.

FIG. (is a top view taken along line 4-4.

FIG. 5,.is a top view showing a second embodiment using the. principlesof the present invention.

Referring now to FIG. I, a pilot hole 1 is drilled into the earth to adepth slightly greater than the desired depth of the large, i.e. 6-25feet, diameter hole. This pilot hole could be drilled by any suitablemeans known in the art such as a rotary rock drill. Next a smalldiameter anchor pipe 2, having an outside diameter between 2 to 6inches, is placed down the pilot hole andanchored to the bottom of pilothole 1. Anchoring can be accomplished by any one of several known meanssuch as a packer assembly 4. If the bottom of the anchor pipe is inrock, the packer assembly will hold, 1f the anchor pipe is in firm soil,an underreamer should be used to roam out about 200 feet at the bottomof the pilot hole. and then a sealing additurc such as plastic is pumpedIt should be noted that after anchor pipe 2 is anchored to the bottom ofpilot hole 1 there will be a portion of the anchor pipe which willextend above the earth's surface for purposes which will be explainedlater.

The drill assembly, as shown in FIG. I, cimsists of two identical augers6 and 7 and a center auger 8 which is located over and rotatable aboutsaid anchor pipe 2 as shown. Augers 6 and 7 are connected to power subsI0 and 12 respectively and auger 8 is connected to a hydraulic powerswivel 14. Power subs l0 and 12 supply rotary motion to the augersthrough shafts l6 and 18 respectively and power subs l0 and 12 may be ofany commercial type known in the art such as the Bowen PS3 Power Subwhich is manufactured by Bowen Tools, Inc., Houston, Texas. Augers inthe present embodiment have a 36-inch diameter but such small diameteraugcrs' may range from 6 inches to 36 inches in diameter.

Rotary power is supplied to auger 8 from hydraulic power swivel 14through shaft 20. Hydraulic povvcrswivel 14 may be of any commercialtype known in the art.

Hydraulic powcrswivel 14 is connected to a hydraulic jack 22 which isconnected to a hydraulic slip 24. As is shown in FIG. 1, anchor pipe 2passes through hydraulic power swivel 14, hydraulic jack 22 andhydraulic slip 24. Hydraulic jack 22 may be of any commercial type knownin the art and should have a 5-foot stroke and a -ton capacity for bestoperation.

Hydraulic pressure is supplied to power sub 10 by hydraulic lines 26 and28 and to power sub 12 by hydraulic lines 30 and 32. Likewise, hydraulicpower is supplied to hydraulic power swivel 14 by lines 34 and 36. Allof these hydraulic lines are connected to hydraulic power sources (notshown) which are known in the art such as hydraulic pumps.

Power subs l0 and 12 are located on a traversing and jacking bar 38. Bar38 contains slots 40 and 42 as shown in FIG. 2. Shafts 16 and 18 fitwithin slots: 40 and 42 respectively and this allows power subs 10 and12 to traverse along bar 38 between the positions shown by power subs l0and 12 and their alternate positions represented by 100 and 120. Powersub 10 is traversed along bar 38 by a hydraulic jack 44 and likewisepower sub 18 is traversed along bar 38 by a hydraulic jack 46 as shownin FIG. 2.

Bar 38 is attached to hydraulic power swivel l4 and also to U-bars 48and 50. U-bars 48 and 50 are in turn connected to auxiliary hydraulicjacks 52 and 54. FIG. 3 shows how power sub 10 can traverse along bar 38to its most extended position as shown by power sub 10a.

Auxiliary hydraulic jacks 52 and 54 are connected to a bar 56. Bar 56 isconnected to hydraulic slip 24 and also to casing jacking rings 58 and60. Casing jacking rings 58 and 60 are attaohed to a casing 62. Inaddition to rings 58 and 60, casing jacking rings 64, 66, 68, and 70 areattached to casing 62 as shown in FIG. 4. These rings continue aroundcasing 62 at uniform intervals and they would be located in a continuousmanner around casing 62 if it were shown. Bar 56 is attached to rings 58and 60 in such a manner that it may be unattached and then reattached toanother pair of jacking rings such as rings 64 and 70. This could beaccomplished in a manner such as attaching bar 56 to rings 58 and 60 byremovable screws.

The operation of my invention as above described is as follows: Afterthe anchor pipe is secured as described above the drilling of the largediameter hole begins. Anchor pipe 2 will extend above the earth'ssurface an amount slightly greater than the height of the drillingapparatus. The drilling apparatus is then attached to anchor pipe 2 andauxiliary hydrau lic jacks 52 and 54 and hydraulic jack 2.2 are in thecontracted or up position. Next hydraulic slip 24 is locked onto anchorpipe 2. Augers 6, 7 and 8 are then set in rotary motion by powersupplied by power subs l0 and 12 and by hydraulic power swivel 14respectively. The augers, are then forced down into the earth's crust byengaging hydraulic jack 22 and auxiliary jacks 52 and 54 toward theirextended positions as shown in FIG. I. The reaction needed for theaction of forcing the augers down comes from the fact that the hydraulicslip is secured to anchor pipe 2 which is anchored into the ground.

Also, after the drill assembly has progressed down into the earth for ashort distance a section of easing'62 may be placed in the hole andattached to bar 56 at jacking rings 58 and 60. The casing will giveadditional weight to the assembly to force the augers down duringdrilling.

After augers 6, 7 and 8 have drilled into the earth up to bar 38,hydraulic jack 22 and auxiliary jacks S2 and 54 are moved into thecontracted or up position, thus raising augers 6, 7 and 8 and leavingholes in the earth where these augers had drilled, Next hydraulic jacks44 and 46 are set in motion and power subs l and 12 are moved along bar38 away from anchor pipe 2. Power subs l0 and 12 should be moved enoughso that augers 6 and 7 are just past the previously drilled hole. Nextthe augers are forced into the earth as described above and the abovesequence is repeated. This above-described operation will continue untilthe augers have drilled holes along a line under bar 38 and when powersubs l0 and 12 are in the outer position as shown by 100 and 12a in FIG.I. As stated above, FIG. 3 shows how the power sub will go under U-bar48 to allow holes to be drilled under the outer edge of bar 38. This isalso true of power sub 12 and U-bar 50.

After a line of holes has been drilled under bar 38 as described above,hydraulic jack 22 and auxiliary jacks 52 and 54 are again put inthe'contracted or up position. Next bar 56 is detached from rings 58 and60 if casing 62 is being used. Hydraulic power swivel 14 is then engagedand the whole drilling assembly is rotated in either a clockwise orcounterclockwise direction. lf the direction was clockwise then thedrill assembly would be moved until bar 56 was under rings 64 and 70.Next, bar 56 is attached to rings 64 and 70 in the same manner as it wasattached to rings 58 and 60.

After the drill assembly is turned, power subs l0 and 12 are moved totheir position, shown as H6. 1, by hydraulic jacks 44 and 46. Once againthe drilling procedure is repeated along the new position of bar 38.After the new line of holes are drilled the whole assembly is rotatedagain. This'drilling of small holes with augers 6 and 7 is continueduntil a large diameter hole is formed.

The loose earth created by the drilling process could be removed in anyone of several conventional ways. One method would be to use a jetengine and create a venturi system whereby the jet engine would create avacuum which would pull the loose dirt up through conduits (not shown)which would extend into the hole.

Once the large hole has been formed from the small holes, hydraulic slip24 is released from anchor pipe 2 and the whole drill assembly pluscasing is lowered to a new position so that augers 6, 7 and 8 may onceagain drill into the earth. This sequence of operations would becontinued until the desired depth of the large diameter hole wasachieved.

FIG. 5 shows a second embodiment of my invention. Here again theprincipal is to drill a large diameter hole by drilling a series ofsmall diameter holes. The basic operation and drill assembly would bethe same as described above but in this embodiment an X-shaped bar wouldbe used and four power subs and four augers.

An X-shaped bar 72 would replace bar 38 of the above assembly and onthis bar would be located power subs 74, 76, 78, and 80. Power sub 74 ismoved along one position of bar 72 by hydraulic jack 82. Likewise powersubs 76, 78, and 80 and casing 62 will be identical as described above.Power sub 78 will be supplied hydraulic power through lines 98 and 100.Likewise, sub 80 by lines 102 and 104, sub 74 by lines 106 and 108, andsub 76 by lines 110 and 112. Also slots "4, 116, 118, and 120 areprovided in bar 72 so that power subs 74, 76, 78, and 80 respectivelymay move back and forth along their position of bar 72. U-bars 122, 124,I26 and 128 are located on the end position of X-shaped bar 72 andauxiliary jacks (not shown) will be located above these U-bars.

The operation of this embodiment would be the same as the drillingapparatus explained above. The main advantage in this embodiment beingthat the small holes may be drilled with one-half the number ofoperations as required by the primary invention. Therefore, the largediameter hole could be dug faster since more augers are employed.

While I have shown and described a workable form of my invention, I wishit to be specifically understood that the same may well be modifiedwithout departure from the scope and spirit ofthe appended claims.

lclaim:

1. Apparatus for drilling a large diameter hole comprising a 2. Anapparatus in accordance with claim I wherein said drilling meanscomprises securing means for securing said drilling means to said pipe,a supporting means for supporting said augers, a pressure means forapplying directed pressure between said supporting means and saidsecuring means and power means attached to said augers for supplyingrotary power to said augers.

3. An apparatus in accordance with claim 2 wherein said supporting meanscomprises a traversing bar and a traversing means for traversing aportion of said power means and said augers along said traversing bar.

4. An apparatus in accordance with claim 3 wherein said traversing baris provided with a series of slots, each slot capable of receiving oneof said power means and said augers and are moved along their positionsof bar 72 by hydraulic jacks 84, 86, and 88 respectively. Anchor pipe 2,hydraulic jack 22 guiding said power means and said augers as theytraverse over said traversing bar.

5. An apparatus in accordance with claim'2 wherein said pressure meanscomprises a series of hydraulic jacks, one of said jacks being securedon said pipe and directing pressure against the center of saidsupporting means and another of said jacks being located between theends of said supporting means and said securing means.

6. An apparatus in accordance with claim 2 wherein said securingmeans'consists of a slidable hydraulic slip and a bar, said bar runningparallel to and being the same length as said supporting means, saidslip being received on said pipe and attaching to said pipe to securesaid drill means.

7. An apparatus in accordance with claim 3 wherein said power meanscomprises a series of hydraulic power subs, one of said subs beingreceived on said pipe and supplying rotary motion to one of said augerswhich is received on said pipe and another of said subs being located onsaid traversing bar and attached to said traversing means.

8. An apparatus in accordance with claim 7 wherein said traversing meanscomprises hydraulic jacks which traverse said subs along said traversingbar.

1. Apparatus for drilling a large diameter hole comprising a pipe ofconstant diameter having a length slightly greater than the desireddepth of the proposed hole, said pipe being adapted to be placed andsecured within a previously drilled pilot hole with a depth greater thanthe proposed hole and with the upper end of said pipe projecting abovethe upper elevation of said pilot hole, a drilling means received uponthe projecting upper end of said pipe, said drilling means having aseries of augers which are capable of drilling a series of smallcontiguous holes to form a large diameter hole.
 2. An apparatus inaccordance with claim 1 wherein said drilling means comprises securingmeans for securing said drilling means to said pipe, a supporting meansfor supporting said augers, a pressure means for applying directedpressure between said supporting means and said securing means and powermeans attached to said augers for supplying rotary power to said augers.3. An apparatus in accordance with claim 2 wherein said supporting meanscomprises a traversing bar and a traversing means for traversing aportion of said power means and said augers along said traversing bar.4. An apparatus in accordance with claim 3 wherein said traversing baris provided with a series of slots, each slot capable of receiving oneof said power means and said augers and guiding said power means andsaid augers as they traverse over said traversing bar.
 5. An apparatusin accordance with claim 2 wherein said pressure means comprises aseries oF hydraulic jacks, one of said jacks being secured on said pipeand directing pressure against the center of said supporting means andanother of said jacks being located between the ends of said supportingmeans and said securing means.
 6. An apparatus in accordance with claim2 wherein said securing means consists of a slidable hydraulic slip anda bar, said bar running parallel to and being the same length as saidsupporting means, said slip being received on said pipe and attaching tosaid pipe to secure said drill means.
 7. An apparatus in accordance withclaim 3 wherein said power means comprises a series of hydraulic powersubs, one of said subs being received on said pipe and supplying rotarymotion to one of said augers which is received on said pipe and anotherof said subs being located on said traversing bar and attached to saidtraversing means.
 8. An apparatus in accordance with claim 7 whereinsaid traversing means comprises hydraulic jacks which traverse said subsalong said traversing bar.